1. Field of the Invention
The present invention relates to an electrical float switch assembly for use in tanks or sumps. The assembly includes an upright support having elongated, recess-defining walls configured to crimpingly engage an outer deformable covering of a float switch electric cord at a preselected height.
2. Description of the Prior Art
Electric float switches for pumps are often used in combination with tanks, sumps and other liquid-holding vessels. In general, such float switches initiate pump operation when the level of liquid reaches a certain height in the tank, and then interrupt operation of the pump after the liquid level falls. In some instances, a second float switch is provided and disposed in overlying relationship to the first switch and is operable to activate a second, backup pump should the first pump fail or otherwise be insufficient for removing liquid from the tank at a proper flow rate. Moreover, a third float switch is occasionally utilized for activating an alarm system whenever the tank liquid level rises to an untolerable height.
As is known, float switches in combination with gravity fed tanks are widely used in various applications, ranging from large scale systems in process industries to smaller scale, commercial or residential use as for pumping sewage or excess ground water. Recently, for example, low pressure sewage systems have become increasingly popular in smaller communities, since holding tanks can temporarily retain a preselected quantity of the sewage and grinder pumps can be intermittently activated to pump the sewage through small diameter, plastic pipe, avoiding the need for major excavation, costly large diameter pipe or other capital intensive components.
Oftentimes, float switches comprise a lightweight, floatable, foam-filled housing internally containing a mercury switch. The switch is electrically connected to an insulated, flexible electric cord, and the latter is secured to a tank sidewall or other support at a certain height and at a distance spaced from the switch housing, such that the length of cord between the point of securement to the tank sidewall and the switch housing enables the switch to freely move in response to any buoyancy forces presented by liquid in the tank. When the liquid level in the tank is below the switch, the latter assumes a somewhat vertical, hanging orientation wherein the switch contacts are open. However, as the liquid level in the tank approaches the height of the switch, the housing is buoyed and the mercury switch shifts to a horizontal orientation, thereby closing the switch contacts and activating the pump or other electrical device. Subsequently, when the water level in the tank falls below the position of the switch, the latter again returns to a more vertical or hanging orientation to simultaneously open the switch contacts and interrupt operation of the pump.
In the past, a variety of methods have been proposed for adjustably positioning the float switch at a preselected height in order to maintain tank liquid levels within certain desired bounds. Typically, a portion of the switch cord is secured at a certain vertical position by an arrangement of hardware including nuts and bolts, and consequently such practice requires a multiplicity of components as well as wrenches and other tools for adjusting the switches in the field. In other cases, the cord is simply tied in an upright support by a rope or wire. Unfortunately, such prior practices do not lend themselves to easy, quick field installation and are generally unsatisfactory in one respect or another.